Newton's Second Law, Gravity and Friction Forces

Scantling and Ball

[M | t | ★★★]
Ball rolling down tilted trough in oscillatory fashion yields acceleration. Also known as Galileo's Inclined Plane).

[In-Depth Description]

Uniform Acceleration

[L | t+ | —]
Glider acceleration by an inclined air track or by a falling weight/string attachment; large ballbearing rolling on PASCO track (with strings).

[In-Depth Description]

Atwood's Machine

[M | t+ | —]
Combinations of weights suspended over pulley to show that asymmetry causes acceleration.

[In-Depth Description]

Double Atwood's Machine

[M | t+ | —]
Prediction of motion of mass in a more complex wheel, axle, and pulley assembly.

[In-Depth Description]

Brachistochrone

[M | t | —] Straight and cycloidal inclined paths, with the ball on the cycloidal path always beating the straight one to the bottom.

[In-Depth Description]

Ball and Strobe

[L | t++ | —]
Ball and Strobe A ball is dropped 5 meters and photographed under stroboscopic illumination.

Newton's Apple

[L | t++ | ★★★★]
Apple electronically released from platform; fall time given by special circuit and digital display.

[In-Depth Description]

Friction Blocks

[M | t | ★]
Selection of blocks that slide down a variable-angle inclined plane to demonstrate the various aspects of friction.

[In-Depth Description]

Locked Brakes

[M | t | ★★★]
The difference between static and kinetic friction can cause the car to skid when braking.

[In-Depth Description]

Rope Friction around Pole

[M | t+ | — ]
The tension force in a rope grows exponentially with the number of turns the rope makes around a pole.

[In-Depth Description]

Resistance to Free Fall

[M | t+ | —]
Ping Pong balls are dropped in air and SF6 for comparison

Nutty Free Fall

[L | t+ | —]
Large nuts linked by threads at different distances (d, 4d, 9d, 16d, 25d, etc.) dropped from platform; sound of landing gives equal time intervals.

Falling Faster than 'g'

[M | t | ★★]
Allow a stick to rotate under the force of gravity and the free end will accelerate at a rate greater than g. Relation between angular acceleration and linear acceleration seems to give free-fall paradox.

[In-Depth Description]

Feather and Dime

[L | t+ | ★★]
Falling in an evacuated tube at the same rate.

[In-Depth Description]

Drop-n-Catch

[L | t+ | —]
Ball drops from mast of PASCO cart; its motion can be considered relative to the moving cart or the track frame of reference.

[In-Depth Description]

Shoot-n-Drop

[S | t+ | —]
Ball shot horizontally, one dropped vertically; both hit the ground at the same time.

[In-Depth Description]

Shoot-n-Catch

[L | t++ | —]
Ball shot up from PASCO cart is caught by same; a puzzler to ponder if track is tilted and cart accelerates down (or decelerates up).

[In-Depth Description]

Shoot the Monkey

[L | t++ | ★★★★]
Monkey released from platform is shot by simultaneously fired cannon.

[In-Depth Description]

Reversible (Kater's) Pendulum

[M | t | ★★]
A physical pendulum with two adjustable knife edges for an accurate determination of "g".

[In-Depth Description]

Potential Well

[M | t | ★]
Orbital motion simulated by ball rolling on wooden potential well.

[In-Depth Description]

Cavendish Experiment

[L | t++ | ★★★★]
Calculation of gravitational constant, with accompanying apparatus model.

[In-Depth Description]

Contact Us

Mailing Address: Lecture Demonstration Services, Science Center, Rm B-08A, 1 Oxford Street, Cambridge, MA 02138
Campus Location: Science Center B-08A | Tel: (617) 495-5824 | Email: scidemos-at-fas.harvard.edu